Analysis of pesticides in dietary supplements: Evaluation of QuEChERS, Cartridge SPE clean-up, and gas chromatography time-of-flight mass spectrometry
New requirements for dietary supplements to be manufactured under cGMP regulations have created a need formethods to detect pesticides in these complex, largely botanical products (e.g. vitamins, herbal and botanical pills, etc.) Sincedietary supplements contain natural products where pesticides have been employed, methods for pesticide analysis must beevaluated, including sample extraction and clean-up as well as instrumental techniques such as gas chromatography (GC). TheQuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) sample preparation method offers a rapid way to prepare samplesfor analysis, but dietary supplement extracts can be so complex as to make trace-level pesticide determinations problematic. Inthis work, we evaluate a method involving QuEChERS extraction and dispersive solid phase extraction (dSPE) clean-up, cartridgeSPE (cSPE) clean-up, and GC- time-of-flight mass spectrometry (TOFMS) to detect pesticide residues in dandelion root powderobtained from a dietary supplement vendor.